Air flow detection and measurement is a necessary and desirable function of most systems that involve movement of air and other gases. This includes detection for the purposes of measurement and control.
Measurement generally requires the detector or other instrument to be in direct contact with the moving air or gas. Impingement of the air or gas on a detector or instrument will disrupt the flow and may adversely affect the measurement.
Representative of the art is U.S. Pat. No. 6,672,152 which discloses an air data sensor for an aircraft has a flush mounted plate at the outside surface of the aircraft and a housing for the sensor within the aircraft below the plate. A plurality of holes in the plate provide air flow to a pressure sensor in the housing. To prevent water from reaching the sensor, a trap chamber is provided below the holes. Various contorted air flow paths are disclosed. The tube to the pressure sensor may be heated.
What is needed is an instrument housing comprising a first portion having a wedge form, a third portion having a wedge form, a second portion between the first portion and the third portion, a first hinge portion between the first portion and the second portion, the first hinge portion extending normal to a major axis A-A, a second hinge portion between the second portion and the third portion, the second hinge portion extending normal to a major axis A-A, and the second portion having a portion for receiving an instrument.